I. Field of the Invention
The present invention relates generally to sensors and more particularly to shaft speed sensors.
II. Description of the Related Art
It is sometimes desirable, in systems that use rotating shafts in bearings, to monitor the rotational speed of the shafts. The monitoring can provide feedback to the system controller regarding the operational status of the shaft. The controller can then vary the speed of the shaft in order to produce the desired effect on the system.
Currently, an analog representation of rotating shaft speed can be generated only from a separate pulse-frequency-output sensor and a pulse-frequency-input to analog-output signal-conditioner module. However, it is desirable to monitor shaft speed using a minimum of components to reduce the size and price of the sensor. Accordingly, there is a need in the art for a self-contained sensor to monitor shaft rotational speed.